i like your channel a lot is very help full but this video had issues, i count 4 caps at the archive at 50 volts and 1000 μf and those caps are missing from the pcb that you demonstrating also, at the pcb there is a12 linear voltage regulator but missing from the archive, i admit that i need a diy robust boost-buck converter but i will not try this one
@ Kasyan TV How come one should Make with the printable PCB schematic preferably on back and white paper to transfer the ink to copper clad No printable copper clad PCB schematic link provided in description No ready made schematic program from eagle or proteus, no link provide in description to download schematic file and you want to order it from JLCPCB ? Without giving the file No list of proper components or you did not mentioned how many turns of magnet copper wound on the ferrite core So that make your project easily, if don't to help us and you just wants views earn from RU-vid, by promoting JLPCB And Promote your own mobile Application for making money Looks like these channel is as Hoax So Best of luck, your channel won't last much longer .
Kasyan, it seems there is a mistake in the schematic: C8 & C9 are not grounded, but connected to the AC side of the secondary. Their positive side also is connected to IRFZ44’s Drain, which may short-circuit it (at first sight). I downloaded “now” (March/2023) the schematic and it shows the same. In case the schematic is correct I would appreciate a brief explanation why it was done as like that. Otherwise, it might be enough to update the Zip file and anchor an “author’s comment” with such update. Thank you for sharing, I’m very fond of your channel!
Look into the circuit of a buckboost converter...It functions always like your circuit. Try that...It only need only one winding insted of two that you used.
I have recreated this boost-buck converter with great interest. Except for 2 modifications, the proposed layout and assembly was used. The right side of the board has been stretched a bit to make room for 10mm diameter capacitors. The diode was replaced by MBR20100 (dual as shown in the layout). The converter works. The coil (core T106-26, 93 nH/N², 2 x 10 turns 1,2mm copper) gets louder with increasing load and hot, really hot, at 2 amps 70 degrees Celsius after 2 minutes. Input 12.1V / 5.2A - Output 13.8V / 2.16A - Efficiency 47% :-( Maximum output voltage with this choke and R1 at 1 kOhm are just under 18 volts at 12 volts input, that's ok. Will test again with 14 turns and different core. Any suggestions (core, heat problem)?
I played around with the converter. I would like to say in advance that this concerns only my built version, I have no expertise and the changes can be completely wrong. Step 1: The most critical component of a DC-DC converter is the choke. At 8,2 kOhm and 2,2 nF, the UC3843 frequency is at ~ 95 kHz. I've added 4 extra turns, almost doubling the mH (from 0,014 mH to 0,024 mH). The winding ist now 2 x 14 turns. A reduction of the resistance from 8,2 kOhm to 6,1 kOhm causes the switching frequency to rise to approx. 125 kHz. Overall, the efficiency has thus increased by almost 7%, but at 54% is still far too low (input 12V / 4.2A - output 13.8V / 2A). Step 2: Control of the power FET. The signal of the UC3843 starts to oscillate under load. A 33 μF capacitor between pin 5 (GND) and 7 (VCC) of the PWM contoller also solved this problem. Efficiency is now just above 62% (input 12.1V / 3.6A - output 13.8V / 2A) I was able to greatly reduce the "noise level" under load by connecting the heat sink on GND. (Check insulation of mounted components!) The heat problem is much less, but still there. The power required at the entrance has dropped by 20 watts, unlike the beginning. I would suggest a larger bobbin and thicker winding (~ 2mm). But for this you could already buy a ready-made buck-boost converter with much higher performance :-( For smaller performance, however, the DIY-module shown is still usable. I changed R1 from 1 kOhm to 4,1 k Ohm to get a voltage range from 4,2V to 24V, thats fine. Thank you
I guess the core heating is due to magnetic saturation. Even for iron powder cores it is not wise to exceed 0.5 T. You can calculate magnetic field strength by multiplying the current with the number of turns and divide it through the magnetic length ( pi/2*(D+d) ). The result must be multiplied by µ0*µr. If the core saturates, the current rises to the current limit or resistive limit. The electric power is converted into heat. This could also be the reason, why the efficiency is so small. The UC3843 is also not capable to drive enough gate current for fast switching of MOSFETs with significant input capacities and gate charges. So it is better to use a gate driver IC behind its output pin, which can deliver at least 2 A in source and sink modes.
It's difficult to have the low ESR capacitors at 110kHZ(C8 ,C9). I think "Flyback Converter" should be much better for diyer.(remove C8 ,C9...and swap the transformer output two pins)
Hi teacher I realy need this circuit so i made it exactlly but it was very bad to charge laptop so i made another circuit with xl6009 ic it is good for laptops charging. Thanks allot .
i repeated this circuit, & it worked flawlessly, soon i'll provide link to that i altered the components according to my availability but, it didn't came in middle of working of the circuit, thank you kasyan tv for sharing this circuit with us
Is it possible to add more mosfets in parallel to gain more power? I want to build MMPT around 60amps at 55v output from solar panels 75v to charge 48v acid lead batteries..4 battery in series im not sure that UC3843 can provide enough power to gates more than one mosfet.what do you think?maybe to add in circuit push pull totem pole for gate of 5 mosfets or more?Can feedback input of UC3843 can handle 55v how would you do that?
I see there are 6 x 1000uF caps on the circuit diag. 4 of them being 50 volt and 2 of them being 25 volt. Yet there are only 2 large electrolytic caps on the board. Is that board an early proto of the final product? What are the inductance of the coils?
I am trying to make this converter with the help of your Circuit Diagram... As someone mentioned in the comments that C8 and C9 goes directly to the mosfet? In your video I can only see 2 caps which I presume are the input and output filter caps. So did you omit C8 and C9 or what?
It has a inbuilt transistor within the chip. You can either tweak the chuop to get the control signal direct or drive your external fet with inbuilt transistor. If later is the case, then so add a emitter follower bjt stage or add a inverter function chip with decent slew rate inorder to provide correct pulse to your external Mosfet.
Capo Boghikian Bhai apko ice room cooler Dy sakta hon 12 volt ka Jo apky 12x12 KY room ko 30 minutes main thanks krdy gha Mera number yeh hy ap muje what's up per bhi contact KR sakty Hain 0335-3775280
I have a similar circuit. It has 120w output. 2 same mosfets used. the first mosfet's drain leg is connected with the second mosfet's source leg. There is a single winding inductance and first mosfet after inductance. The first mosfet's source leg given to the ground. I understand the situation when mosfets are connected in parallel, but can you explain the situation when connected in series? As in the circuit i tried to explain... Is there such a video?
sir kasyan one thing i will ask before doing this circuit what is the voltage feedback on this uc3843 what voltage you set to R3? pleasse answer me.. i want to know im a hobbiest im truggling understanding the datasheet in voltage feedback....
Hi Mam (Kaasyan). I am a hobbyist I made the above circuit it is working but as i put load the output current drops down. I need 5A to drive 2Nos 775 Motors which I am not getting. Could you suggest what to doooooooo. my circuits all electrolite caps are 1000mfd/50V. any change?. This circuit is for my RC Boat. Power source is Lion battery 11.1V 5400mAh to boost 12 to 24V 5A. Your help will be very needfull. Thanks.
Hello Friend. Do you have more references about the calculation for the inductor? I'm looking for all the conciderations needed to calculate those coupled inductors. Can anybody help me please?
how do i take advantage of the free shipping on first order? i tried placing order once and it shows that i have to pay 18.60 US dollars for the shipping
This seems to be Flyback topology . Am i right ? If yes then how come there's no air gap in between the core. I m assuming that the effective air gap caused by the powdered metal core is sufficient to store energy. If someone gets this please let me know.
